Rotary tower crane suitable for highway transportation

ABSTRACT

A rotary tower crane which can be converted from an operating mode in which the crane boom extends transversely beyond the vertical axis of the crane tower to a mode suitable for transportation of the crane, in which mode the boom is at least partially housed within the tower of the crane. The boom and upper portion of the tower include apparatus which enables the boom to move to a position substantially coaxial with the axis of the tower, from which position at least a portion of the boom is telescoped into the tower of the crane.

United States Patent 1191 1111 3,863,773 Reich et al. Feb. 4, 1975 [5ROTARY TOWER CRANE SUITABLE FOR 3,252,585 5/1966 Wieschel 212/144HIGHWAY TRANSPORTATION FOREIGN PATENTS OR APPLICATIONS lnvefltorsi ElmarReich, Biberach an der RiSS; 967,911 3/1963 Great Britain 212/46 BAlfons Kohle, Pflummernstrasse, 276,437 0/1962 Netherlands 212/144 bothof Germany [73] Assignee: Hans Liebherr, Biberach an der PrimaryExami'fe" stanley Tonbel'g Riss, Germany Assistant ExammerH. GrantSkaggs, Jr. I Attorney, Agent, or FirmEdward R. Weingram, Esq. [22]Flledz July 9, 1973- [21] Appl. No.: 377,757 [57] ABSTRACT A rotarytower crane which can be converted from an [30] Foreign ApplicationPriority Data operating mode in which the crane boom extendstransversely beyond the vertical axis of the crane July 10,1972 Germany2233828 tower to a mode suitable for transportation of the crane, inwhich mode the boom is at least partially 212/46 housed within the towerof the crane. The boom and [58] Fie'ld B 64 33 upper portion of thetower include apparatus which 5 enables the boom to move to a positionsubstantially coaxial with the axis of the tower, from which position[56] References Cited at least a portion of the boom is telescoped intothe UNITED STATES PATENTS tower of the 3,189,189 6/1965 Waetun et al212/46 B 7 Clalms, 2 Drawmg Flglres PATENTEDFEB 4mm 3.863.773

SHEET 1 UF 2 Fig.1

PATENT FEMIQB 3,863,773

' SHEET 2 [IF 2 ROTARY TOWER CRANE SUITABLE FOR IIIGIIWAY-TRANSPORTATION BACKGROUND OF THE INVENTION 1. Field of the InventionThis invention relates to hoisting apparatus and, more particularly,rotary tower cranes which can be collapsed to facilitate transportationof the crane from one location to another.

2. Description of the Prior Art Rotary tower cranes have becomeincreasingly popular in the construction field and they have beendeveloped in several different embodiments for many varied uses. Thesecranes consist, essentially, of a vertical tower and a boom, pivoted tothe tower. Some of the booms, often referred to as needle-type booms,can be adjusted with respect to the horizontal inclination of the boom,while other booms, often referred to as crabtype booms, tend to have afixed horizontal attitude with a crab moving along the length of theboom. The tower of the crane and/or the boom is often composed ofseveral detachable sections, which can be added or taken away in orderto adjust the length of either the tower or the boom.

It is desirable to be able to easily move these rotary tower cranes fromone site of use to another, without completely disassembling the craneinto its basic component parts and then reassembling it at the new site.Many different cranes have been developed to facilitate thetransportation of the crane. Most of the prior art attempts haveprovided a rotary tower crane which is converted from an operating modeof use to a transportation mode of use by, in some manner, placing thetower of the crane in a horizontal position with the crane bo'om swungparallel to the tower, lying either above, below, or alongside thetower. Several sections of the tower are often formed so that they canbe telescoped in order to shorten the length of the tower. Also, wherethe boom is composed of two or more sections, very often the separatesections of the boom are hinged so that they can be folded to be placedin a more compact arrangement. In some circumstances, both the tower andthe boom have hinged sections and both the tower and the boom are foldedupon each other and then laid parallel to each other alongside or invertical relationship. However, in all of the prior art, the towercrane, when placed in the compact or transportation mode, still has asubstantially larger cross-sectional and/or length dimensions than doesthe crane when assembled in the operating mode.

SUMMARY OF THE INVENTION In order to overcome the problems set forth inthe prior art, the present invention provides a rotary tower crane whichcan be converted from an operating mode in which the boom extendstransversely boyond the vertical axis of the crane tower to atransportation mode in which the boom of the crane is at least partiallyhoused within the crane tower. The boom and the upper portion of thecrane tower include apparatus which enables the boom to move to aposition substantially coaxial with the axis of the tower and thentelescope at least partially into the tower.

Accordingly, in view of the above, it is an object of the presentinvention to provide a rotary tower crane which can be easily adaptedfor highway transportation and which takes up a minimum of space whenarranged in a mode for transportation.

Another object of the present inventions is to provide a rotary towercrane, which can be quickly and easily converted from an operating modeto a transportation mode.

It is a further object of the present invention to provide a rotarytower crane which is relatively selfcontained and requires a minimum ofexternal equipment to convert the apparatus from the operating mode tothe transportation mode.

Still another object of the present invention is to provide a rotarytower crane in which the hoisting apparatus employed in the operatingmode of the crane is used in effecting the conversion of the cranebetween the operating mode and the transportation mode.

It is yet another object of the present invention to provide a rotarytower crane which does not require disassembly of the boom from thetower during conversion between the operating mode and thetransportation mode of the apparatus.

An additional object of the present invention is to provide a rotarytower crane which does not require extensive specialized equipment forconverting between the operating mode and the transportation mode of theapparatus.

It is another object of the present invention to provide a rotary towercrane which allows the crane boom to be telescoped into the crane towerto provide an assembly having minimum dimensions for purposes oftransportation.

A further object of the present invention is to provide a rotary towercrane which allows the crane boom to be telescoped into the crane towerwithoutdisassembly of the boom from the tower during conversion from onemode of operation to the other.

It is still another object of the present invention to provide a rotarytower crane which can use the operating cab of the crane as a guide forthe crane boom during conversion of the crane from the operating mode tothe transportation mode of the crane.

Yet another object of the present invention is to provide a rotary towercrane which can be converted between the operating mode and thetransportation mode with a minimum of operating personnel.

Another object of the present invention is to provide a rotary towercrane which can be converted between operating and transportation modesand provides a minimum corss-sectional area when arranged in thetransportation mode. v

It is a further object of the present invention to provide a rotarytower crane which is convertible between operating and transportationmodes and has a minimum length when in the transportation mode.

Still another object of the present invention is to provide a rotarytower crane, convertible between an operating mode and a transportationmode, which is relatively rugged and durable, and relatively inexpensiveto fabricate.

It is yet another object of the present invention to provide a rotarytower crane covertible between an operating mode and a transportationmode, in which the sections of both the boom and the tower can beshortcned by telescoping and then the telescoped sections of the boomdrawn within the telescoped sections of the tower, to provide minimumlength and width dimensions of the apparatus for pusposes oftransporting the apparatus from one site of use to another.

Additionally, it is a further object of the present invention to providea rotary tower crane convertible between operating and transportationmodes, which provides apparatus to guide the boom into the tower duringthe telescoping portion of the conversion from the operating mode of thecrane to the transportation mode of the crane.

Another object of the present invention is to provide a rotary towercrane convertible between an operating mode and a transportation mode,which includes apparatus for moving an operating cab within the tower ofthe crane to guide in telescoping the boom of the crane into the towerduring conversion from the operating mode of the crane to thetransportation mode of the crane.

Other objects and advantages will be apparent from the followingdescription of several embodiments of the invention, and the novelfeatures will be particularly pointed out hereinafter in connection withthe appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts a portion of a rotarytower crane built in accordance with the teachings of the presentinvention, showing the top portion of the crane tower and the adjacentportion of the boom, with the boom positioned in the operating mode ofthe crane.

FIG. 2 shows a similar portion of another embodiment of a rotary towercrane built in accordance with the teachings of the present invention,in which the boom is moved to the vertical position prior to beingtelescoped into the tower of the crane to convert the crane to thetransportation mode.

DESCRIPTION OF THE PREFERRED EMBODlMENTS:

While the device will be described below in connection with rotarytypecranes, having normally horizontal crabtype operating booms, it shouldbe pointed out that the invention described herein can also be appliedto rotary tower cranes having needle-type booms.

Further, for purposes of simplicity, the same elements shown indifferent figures of the drawings, will be identified with the samenumerical designation.

Referring to FIG. 1, a rotary tower crane is shown, having a boom,generally indicated at l, substantially horizontally mounted on top of avertical tower, generally indicated at 2. A crab, generally indicated at4, including a hoist block 4', is drawn by means of a tackle line 5along a set of rails 3 mounted on the bottom portion of the horizontalboom. The boom 1 is braced by means of a line 6 connected at one end toan anchoring point 6 (see FIG. 2) on the boom and connected at its otherend to an upper corner of a triangular trestle member or boomarticulating means 7. The second upper end of the triangular trestlemember 7 is an anchoring point for a line 8, which exerts acounterclockwise motion on the trestle to balance the pull from line 6.The third corner of the trestle is connected to the triangular bracing2' at the head of the tower so that the entire trestle 7 and,additionally, the entire boom 1 can revolve about an axis 9 which isperpendicular to the ve t ca axisgflhetowerl- A guide truck 10 isconnected to the head of vertical tower 2 by means of a swing arm 12which pivots with respect to the tower at pivot connection 13, the axisof which connection is parallel to the pivoting axis 9 of the connectionbetween the triangular trestle, 7 boom 1 and the tower support brace 2.A plurality of wheels or rollers 11 are mounted in the guide truck 10 tocontact the track 3, to guide movement of the boom with relation to thevertical tower to be described below.

In order to convert the rotary tower crane from the operating mode withthe boom extending transversely beyond the longitudinal axis of thevertical tower, as shown in FIG. 1, to the transportation mode, in whichthe boom will be telescoped within the vertical tower, it is necessaryto swing the boom about pivot point 9 until the boom is substantiallycoaxial with the rotary tower, as shown in FIG. 2. This is accomplishedby tensioning line 8, which will exert a counterclockwise force on thetriangular trestle, causing the trestle and, therefore, line 6 to rotatecounterclockwise moving the boom in a counterclockwise direction.Simultaneously, the swing arm 12 connected to the guide truck 10 willpivot about axis 13 to be in a position to guide the boom into the towerduring the telescoping operation.

Once in the guiding position, the guide truck 10 or the swing arm 12 islocked. In order to allow for the telescoping of the boom, theconnection at the axis of rotation 9 between the boom and the triangularbracing 2 at the head of the tower is loosened, the boom being supportedby line 5, as described below.

When the boom 1 has been raised to the vertical position, the rollers 14located at the bottom or end of the boom will be engaged with the tackleline 5 of the crab 4. The tackle line 5 is held in operative position bymeans of a guide pulley 5' so that once the boom is in the verticalposition, it can be telescoped into the tower by merely feeding tackleline 5 over the tackle pulley 5 to increase the length ofthe tackle line5. Line 5 can be connected to the boom in any convenient, conventionalmanner. For purposes of the present invention, it is only necessary thatone point of line 5 be held fixed with relation to the boom so that theline can be lengthened or taken up from the end descending verticallybeyond pulley 5. Therefore, since the crab 4 is drawn by means ofline 5,a portion ofline 5 can be held fixed with relation to the boom bylocking crab 4 with respect to the boom and locking hoisting block 4' tothe crab 4 or connecting it to the boom. Of course, line 5 could beconnected directly to boom 1 anywhere along the boom by direct fasteningsimilar to that shown for line 6 to point 6 in FIG. 2. When the boom hasbeen fully telescoped into the tower to the desired length, then thetower can be lowered from the vertical position to the horizontalposition (by means not shown in the drawing) and the entire crane is inthe transportation mode, ready for highway transportation.

As shown in FIG. 2, many cranes have an operators cab 15 mounted withinthe tower which can be moved in the tower to compensate for changes ofheight in the tower. As shown in FIG. 2, the cab 15 is detachablyconnected by means of supporting structure 16 to the tower support braceassembly 2 to maintain the tower cab in a position underneath the boomduring operation. When the rotary tower crane has this type of a cab,the entire cab can be moved down into the tower during the telescopingoperation of the boom by merely detaching the supporting structure 16from the tower supporting brace structure 2 and connecting it instead tothe structure of the boom 1 as, for example, at points 17 where thesupporting structure 15 passes the rear framework of the boom 1. Thesupporting structure 16 can be detachably connected to the tower supportbrace assembly 2' as well as to the framework of the boom at points 17by any convenient meams well known in the state of the fastening art.The cab will then ride down into the tower with the boom. Further, ifguide apparatus for raising and lowering the cab is provided for the cabeither inside the tower or on the cab (not shown), it is possible to usethe guide apparatus for the cab as a guide in telescoping the boom intothe tower. This is accomplished by merely connecting the cab to theboomand then using the cab as a lead for the boom into the tower. Thisguide function for the cab could be in addition to or could replace theguide function of the'guide truck coacting with boom rails Erecting therotary tower crane from the transportation mode to the operating modeoccurs in the reverse sequence described for the conversion from theoperating mode into the transportation mode.

There are other embodiments of the invention which have not been shownin the drawings for purposes of brevity, since they can readily beexplained without recourse to additional figures. For example, asmentioned previously, the guide truck 10 and swing arm 12 can beeliminated in embodiments in which the operators cab 15 is used as aguide for drawing the boom into the rotary tower.

While the drawings do not show the apparatus for ro tating the boomabout the longitudinal axis of the tower, several different apparatusesfor accomplishing this purpose could be compatibly used with theapparatus shown for pivoting the boom from the horizontal position tothe vertical position for telescoping into the tower. So, for example,an axially rotatable section for the tower could be provided, whichwould work either in conjunction with or allow axial rotationindependently of the base section of the tower used for pivoting theentire tower from the vertical to the horizontal position. Additionally,the head of the tower or any other intermediate section of the towercould include a section capable of providing the axial rotation of thetower necessary for rotating the boom about the tower in the operatingmode.

Further, both the tower and the boom can be formed from severalsections, which sections can either be detachable or telescopable. lfdetachable, then intermediate sections of the boom and/or tower can beremoved for purposes of shipping or changing the size of the crane inthe operating mode. If these sections are telescopable, then either theboom and/or the tower can be telescoped separately prior totransportation and then, in turn, the telescoped boom and/or tower canbe placed in the telescope relationship with each other to provide for aminimum of space when arranged in the transportation mode. For acompletely telescoped assembly, the largest boom section would have tobe smaller than the smallest telescoping tower section so that theentire boom could lie within the telescoped sections of the tower whenthe entire assembly is in the fully telescoped position. Further, acompound configuration for the tower would also be compatible with theteachings of the present invention, so that, for example, the towercould be composed of a lower section of substantially greater crosssection and a second upper portion having sections of substantiallysmaller cross sections including a rotary head for the tower, all ofwhich sections could then be telescoped within the larger sections andthen the boom telescoped down with the telescoped tower.

lt will be understood that various changes in the details, materials andarrangements of parts which have been herein described and illustratedin order to explain the nature of the invention may be made by thoseskilled in the art within the principle and scope of the invention, asexpressed in the appended claims.

What is claimed is:

l. A tower crane comprising:

a tower having a lengthwise axis adapted to stand vertically duringhoisting operations of said crane;

a boom for hoisting, having a lengthwise axis adapted to extendtransversely from the lengthwise axis of said tower during hoistingoperations of said crane;

means supporting said boom in said transverse position during hoistingoperation of said crane;

means to move/said lengthwise axis of said boom to a positionsubstantially coaxial with said lengthwise axis of said tower,comprising:

boom actuating means extending transverse from the lengthwise axis ofsaid boom;

means pivotally connecting said boom actuating means to said tower;

means connecting said boom actuating means to 4 said boom; and

means to pivot said boom actuating means about said tower to raise saidboom and thereby bring said lengthwise axis of said boom into alignmentwith said lengthwise axis of said tower; means to move said boom atleast partially into said tower in coaxial telescoped relationship tosaid tower, comprising: line means operatively associated with said boomfor hoisting operation of said crane;

guide means connected to said tower and adapted to hold said line meansin contact with a guide means on said boom;

guide means on said boom vertically spaced when said boom isin itshorizontal positions, said guide means adapted to engage said line meanswhen said-boom is disposed with its lengthwise axis aligned with saidlengthwise axis of said tower; and

said tower guide means and said boom guide means relatively disposed toallow said boom to move into and out of said tower upon lengthening andshortening of said line means; and

means to guide movement of said boom when moving into and out oftelescope relationship with said tower.

2. The tower crane according to claim 1 wherein said means to guide saidmovement of said boom into and out of said telescoping relation withsaid tower comprise:

guide truck means adapted to coact with said boom to guide movement ofsaid boom; and

means pivotally connecting said guide truck means to said tower toposition said guide truck means to guide said boom for telescopingmovement with relation to said tower.

3. The tower crane according to claim 1 wherein said means to guide saidmovement of said boom into and out of said tower comprise:

an operator cab means disposed within said tower and movable along thelengthwise axis of said tower;

means rigidly connecting said operator cab means to said boom to enablesaid cab means to act as a guide for movement of said boom intelescoping relationship with said tower.

4. The tower crane according to claim 3 wherein said means to guide saidmovement of said boom into and out of said tower comprise:

guide truck means adapted to coact with said boom to guide movement ofsaid boom; and

means pivotally connecting said guide truck means to said tower toposition said guide truck means to guide said boom in telescopicmovement with relation to said tower.

5. The tower crane according to claim 1 wherein said boom includes:

a crab means movable along the length of said boom;

and

said line means is included in the tackle for said crab means.

6. The tower crane according to claim 5 wherein:

said means to guide said movement of said boom into and out of saidtower comprise:

guide truck means adapted to coact with said boom to guide movement ofsaid boom; means pivotally connecting said guide truck means to saidtower to position said guide truck means to guide said boom intelescopic movement with relation to said tower; and further comprising:

rail means positioned on said boom means for movement of said crab meansalong said boom; and said rail means coacting with said guide truckmeans for movement of said boom means in telescoping relationship withsaid tower means. 7. The tower crane according to claim 6 wherein saidmeans to guide said movement of said boom into and out of said towercomprise:

an operator cab means disposed within said tower and movable along thelengthwise axis of said tower; and 7 means rigidly-connecting saidoperator cab means to said boom means to enable said cab means to act asa guide for movement of said boom in telescoping relationship with saidtower.

1. A tower crane comprising: a tower having a lengthwise axis adapted tostand vertically during hoisting operations of said crane; a boom forhoisting, having a lengthwise axis adapted to extend transversely fromthe lengthwise axis of said tower during hoisting operations of saidcrane; means supporting said boom in said transverse position duringhoisting operation of said crane; means to move said lengthwise axis ofsaid boom to a position substantially coaxial with said lengthwise axisof said tower, comprising: boom actuating means extending transversefrom the lengthwise axis of said boom; means pivotally connecting saidboom actuating means to said tower; means connecting said boom actuatingmeans to said boom; and means to pivot said boom actuating means aboutsaid tower to raise said boom and thereby bring said lengthwise axis ofsaid boom into alignment with said lengthwise axis of said tower; meansto move said boom at least partially into said tower in coaxialtelescoped relationship to said tower, comprising: line meansoperatively associated with said boom for hoisting operation of saidcrane; guide means connected to said tower and adapted to hold said linemeans in contact with a guide means on said boom; guide means on saidboom vertically spaced when said boom is in its horizontal positions,said guide means adapted to engage said line means when said boom isdisposed with its lengthwise axis aligned with said lengthwise axis ofsaid tower; and said tower guide means and said boom guide meansrelatively disposed to allow said boom to move into and out of saidtower upon lengthening and shortening of said line means; and means toguide movement of said boom when moving into and out of telescoperelationship with said tower.
 2. The tower crane according to claim 1wherein said means to guide said movement of said boom into and out ofsaid telescoping relation with said tower comprise: guide truck meansadapted to coact with said boom to guide movement of said boom; andmeans pivotally connecting said guide truck means to said tower toposition said guide truck means to guide said boom for telescopingmovement with relation to said tower.
 3. The tower crane according toclaim 1 wherein said means to guide said movement of said boom into andout of said tower comprise: an operator cab means disposed within saidtower and movable along the lengthwise axis of said tower; means rigidlyconnecting said operator cab means to said boom to enable said cab meansto act as a guide for movement of said boom in telescoping relationshipwith said tower.
 4. The tower crane according to claim 3 wherein saidmeans to guide said movement of said boom into and out of said towercomprise: guide truck means adapted to coact with said boom to guidemovement of said boom; and means pivotally connecting said guide truckmeans to said tower to position said guide truck means to guide saidboom in telescopic movement with relation to said tower.
 5. The towercrane according to claim 1 wherein said boom includes: a crab meansmovable along the length of said boom; and said line means is includedin the tackle for said crab means.
 6. The tower crane according to claim5 wherein: said means to guide said movement of said boom into and outof said tower comprise: guide truck means adapted to coact with saidboom to guide movement of said boom; means pivotally connecting saidguide truck means to said tower to position said guide truck means toguide said boom in telescopic movement with relation to said tower; andfurther comprising: rail means positioned on said boom means formovement of said crab means along said boom; and said rail meanscoacting with said guide truck means for movement of said boom means intelescoping relationship with said tower means.
 7. The tower craneaccording to claim 6 wherein said means to guide said movement of saidboom into and out of said tower comprise: an operator cab means disposedwithin said tower and movable along the lengthwise axis of said tower;and means rigidly connecting said operator cab means to said boom meansto enable said cab means to act as a guide for movement of said boom intelescoping relationship with said tower.